#include <iostream>
#include <string>
#include <cctype>
#include <vector>

using namespace std;

// Function to check if a name contains any special characters
bool contains_special_characters(const string& name) {
    for (char c : name) {
        if (!isalpha(c) && !isspace(c)) {
            return true; // Special character found
        }
    }
    return false; // No special characters
}

int main() {
    int n;
    cin >> n;
    cin.ignore(); // To ignore the newline character after the integer input

    vector<string> visitors;
    string name;

    // Reading visitor names
    for (int i = 0; i < n; ++i) {
        getline(cin, name);

        // Validate name
        if (contains_special_characters(name)) {
            cout << "Invalid input" << endl;
            return 0;
        }

        visitors.push_back(name);
    }

    // Printing visitor names in the order they were added
    for (size_t i = 0; i < visitors.size(); ++i) {
        cout << visitors[i];
        if (i < visitors.size() - 1) {
            cout << " ";
        }
    }
    cout << endl;

    return 0;
}